Synchronizing two internal combustion engines



Nov. 8, 1932. w. PROFITLICH SYNCHRONIZING TWO INTERNAL COMBUSTION ENGINES Filed Sept. 6, 1930 Patented Nov. 8, 1932 UNITED STATE-S xmL-emnm, cam

TW O INTERNAL COHBUSTIOIT ENGINES Application filed September 8, 1880, Serial 1T0.

which is acted upon by the two crank shafts of the engines, and the equalizing motion of which, upon one of the crank shafts leading or lagging, acts upon the governor and thereby on one or both of the engines until the two crank shafts will have reached again their mutual original. position.

4 In order that the invention can 'be more readily understood, an embodiment of the apparatus is illustrated by way of example in the accompanying drawing in which Figure 1 is an end view of two marine in- I ternal combustion engines equipped with the equalizing gear according tothe invention, Figure 2 1s a longitudinal section through the equalizing gear, on an enlarged scale,

Figure 3 is a cross section on line 33 of F1 re 2, and i Em-e4 is a sectional view through a hydra "c piston-gear acted u on by .the equal- .izer and in turn acting on t vice of the engines. I

Referring to this drawing, A and B denote the two engines of a vessel, and C' and D .denote their crank shafts. E denotes the ease governing de- The vel wheels fand f are driven through their shafts G and H-by the crank shafts C and D, respectively, while the bevel wheels f d run on a common shaft K mounted within a hollow rotary slide J. This slide J rests oil-ti htly in the cylindrihal portion of the casin and serves to control a quantity of oil u gar pressure which enters'the casing E-thro' gh inlet 6 and leaves-it at e. The slide J hasan annular passage 1' extending ing of the equalizing or difierential gear F com rising four bevel wheels f, f, f, f,

'slide'J'is at r 480,219, and in Germany September 27, was,

on thegreater portion of its periphery, and a radia bore 2" disposed between the ends of passage 5 These ducts serve to control the oil underressure contained in the casin E. Upon sli c J being turned out of its middle position the ducts i, i connect passages e, e of the casing E ina determined manner to the inlet e and outlet 0 thereof. These pas; sages e, e respectively, communicate through pipes with the upper space I and the U lower space I of a cylinder, Figure 4, in which a piston L may rise or lower, which acts upon the governing shaft m of the fuel pump M. A 1 The described apparatus operates as folows:

' The crank shafts C and D are rigidly coupled, according'to the experiences of the service or on the basis of calculations of the vibrations, with the shafts G and H in a position in which d11ll1 run the vibrations of thevessel are reduce to a minimum or no vibration at all exist. With this position of the crank shafts the slide J of the equalizing gear is in the middle position illustrated in igure 3 and obturates the assage e and 0 leading to the controlling ston L. Consequently piston L cannot s ift in any direction.

The ratio of transmission between the crankshaftsC and D'and the bevel wheels f and 'f" drivenby them is 2: 1. Now, upon one of the two crank shafts making one revolution so as to assume again its initial position, the slide J executes likewise one revolu- 35 tion and a ain assumes its original middle position. t results'therefrom that if slide J is in middle position the crank shafts C and D take always their determined relative position. It is further to that ifthe two e n from the figi1res run at the same rate,

"'d that/if the relative position of the cranks of the engines doesriot correspond to the determined one, 'th gslide its middle'positio'n,

ay be assumed for instance 'that'the cr shaft D has some lead with-re rd to crankshaft O, then slide J has turn" out of its middle position in clockwise direction so that its passage 2' communicates with the casing passage e while its annular passage 2' communicates with passage e. Consequently the oil under pressure entering the casing E at e flows through passage 2' and passage c to the space 1 above piston L and lowers the latter, since the oil in space Z can escape through passage e annular passage 71 and outlet e The downward motion, of piston L causes a turning motion of the governing shaft m in such a manner that the suction valves of the fuel pump M are opened earlier and the run of engine B is retarded due to the reduced fuel supply, so that slide J returns to middle position. When,'for instance, in turning over the rudder of the vessel, the engine B runs more quickly than engine A, slide J turns again in clockwise direction. As soon as it has turned an amplitude corresponding to this surplus speed, the controlling piston L acts in the above described manner upon the fuel pump M whereby the run of engine B is retarded. Consequently slide J returns to middle position. When a state of stability is reached, slide J remains in middle position, if not so, it turns until piston L moves in opposite direction and anew accelerates the run of engine B.

Probably the slide J and thus the engines A and B will oscillate about the desired crank position.

The apparatus illustrated in the drawing works only if the two crank shafts C and D revolve in the direction of the arrows corresponding to the forward run of the vessel. In working the vessel" for reverse operation the apparatus must be thrown out of operatlon which is effected by releasing the pres sure exerted upon the oil. When for reverse operation the apparatus is not thrown out, then the equalizing gear J acts in opposite sense, that is, any differences in the rates of revolution and in the mutual position of the cranks are not eliminated but increased. 6 In the service of the engines the apparatus ls'thrown into operation, afterv the engines have been set 'to approximately equal rate by hand regulation, at that moment where the disappearance of the vibrations of the vessel lndicates that the crank shafts of the zwo engines are in the desired relative posi- Ion.

The arrangement as described may be modlfied 1n so far as the controlling piston L may act upon the governing shafts of both engines, or another controlling piston L may be'provided for the governing shaft of engine Awhich piston acts upon the fuel pump in a sense opposite to that of engine B.

What I claim, is

' 1, In combination with a power plant comprising two internal combustion engines, crank shafts in said engines, means for synchronizing said engines comprising an equalizlng gear connected between said crank shafts, a governing device for modifying the relative speeds of said engines, and hydraulic pressure means for operating said governing device controlled by said equalizing gear to maintain a synchronous relationship between said engines. 4

2. In combination with a power plant comprising two internal combustion engines, crank shafts in said engines, a chamber containing a fluid under pressure, transmission elements extending from said crank shafts to said chamber, a rotatable element in said chamber adapted to beactuated by a difl'erential movement of said transmission elements, a governing device for modifying the speed of one of said engines with respect to the other, a member operated by a fluid under pressure connected between said governing device and .saidchamber, and valve means in said chamber for controlling said member and governing device by the movement of said rotatable element.

3. In combination with a power plant comprising two internal combustion engines, crank shafts in said engines, a chamber containing a fluid under pressure, transmisison elements extending from said crank shafts to said chamber, a rotatable element in said chamber adapted to be actuated by a differential movement of said transmission elements, a governing device for modifying the speed of one of said engines with'respect to the other, a fluid pressure controlled piston connected to said governing device, a chamber for said piston having ports for a fluid under pressure above and below said piston, communicating conduits between said ports and said'chamber, a normally obturated channel in said chamber associated with an intake pressure adapted to register alternatively with one of said conduits responsive to the direction of actuation of said rotatable element, and another normally obturated channel associated with an exhaust pressure .adapted to respectively register with the other of said conduits responsive to said actuation.-

The foregoing specification signed at Ham burg, Germany, this 23rd day of August. 1930.

W'ILHELM PROFITLICH. 

